This invention relates to abrasive bodies for use as wear parts, cutting tool inserts and the like.
Abrasive compacts are used extensively in curing, milling, grinding, drilling and other abrasive operations. They generally contain ultrahard abrasive particles dispersed in a second phase matrix. The matrix may be metallic or ceramic. The ultrahard abrasive particles may be diamond or cubic boron nitride (CBN). These particles are known to bond to each other during the high pressure and high temperature compact manufacturing process generally used, forming a polycrystalline mass. The bodies so produced are thus also known as PCD or PCBN.
Examples of diamond and cubic boron nitride abrasive compacts are described in U.S. Pat. Nos. 3,745,623; 3,767,371; 3,743,489; and 4,334,928.
For example, U.S. Pat. No. 4,334,928 teaches a sintered compact for use in a tool consisting essentially of 80 to 20 volume percent of high pressure form boron nitride; and the balance being a matrix of at least one binder compound material selected from the group consisting of a carbide, a nitride, a carbonitride, a boride and a silicide of a IVa or a Va transition metal of the periodic table, mixtures thereof and their solid solution compounds; the matrix forming a continuous bonding structure in a sintered body and where the high pressure boron nitride is interspersed within a continuous matrix.
Refractory ceramics have been synthesized at relatively low temperatures and ambient pressures by pyrolyzing organic precursors. Sintered ceramic bodies of various shapes may be produced by utilizing this route. The following papers describe such processes:
1. Wright, J. K. and Evans, J. R. G., Br.Ceram. Trans. J., 89, 163-167, 1990.
2. Interrante L. V. et al, Mat. Res. Soc. Symp. Proc. Vol. 249, 31, 1992.
3. Paine R. T. et al, Polymer Preprints, Vol. 34 No. 1, 336, 1993.
4. Seyferth D. et al, J. Am. Ceram. Soc., 75(5), 1300, 1992.
5. Bouillon E. et al, J. of Mat. Sci., 26 1333, 1991.
6. Soraru G. D., et al, J. of Mat. Sci., 25, 3886, 1990.
7. Gilbert M. Brown and Leon Maya T., Amer. Ceram. Soc. 71, 78-82 (1988).
Diamond grinding wheels comprising a mass of diamond particles dispersed in a ceramic matrix are also known in the art.